Got to get the priors first, if someone doesn't understand the need for individual sovereignty, they can't understand why people are responsible and rational enough to have the freedoms that Bitcoin provides. Otherwise the argument ends up being justification: "Well, people are good at this, so they should be allowed to do this, but they shouldn't be allowed to do that." That's a stalemate.
Go for philosophy.
E.G. If you're thinking about kids, think about the world you want your kid to live in.